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Monday, August 27, 2012

SDO takes pictures of the Sun in many wavelengths and uses the polarization of the light to measure the magnetic field of the Sun. Then we are forced to rely on the human eye to look at our images. The human eye uses three color sensors to see millions of colors. We don’t see polarized light any different than non-polarized without special sunglasses. Polarized light has the light waves moving in one direction. Glare is light moving side-to-side so sunglasses that let light through that is moving up and down can keep glare out of your eyes. But we usually don't worry about polarized light.

Is there an eye that could better enjoy SDO images? Yes! The
mantis shrimp.

These arthropods have up to 12 different color sensors and can see light from the ultraviolet to the infrared (see an amazing closeup of the eyes at the National Geographic.) Two channels see shapes and the rest look at colors. One set of eye cells can measure the polarization of the light. They can see about 10 times more colors over a wider range of
wavelengths than humans.

Rather than the 3-color composites we now display (such as this one from today), we could display AIA and HMI images in a 12-color display. A mantis shrimp might enjoy
watching for flares and coronal mass ejections!

We don’t understand why a mantis shrimp needs this optical equipment. They live in the brightly colored tropical oceans. Maybe they need to see the differences between friend, foe, and food. Some fish glow in ultraviolet light, perhaps that is another signal the shrimp watch for. The polarized light might reveal semi-transparent fish to a hungry mantis shrimp. Sounds like they have their own real-time feature finding team built into their eyes.

Perhaps we could adapt the multi-wavelength viewing used by
the mantis shrimp to find out what is happening on the Sun.

Check out the July 30, 2012 episode of RadioLab to hear more
about how different animals see color.

Monday, August 20, 2012

The air conditioning at Stanford has been repaired and images are once again flowing to the right places. While the 48 hours of catchup is being played some images may be seen in the wrong order as a `latest' file. This is normal during the replay of the telemetry but the usual flow should be seen tomorrow morning.

Saturday, August 18, 2012

Late last night the air conditioning at Stanford University stopped. HMI & AIA images will not be available until the problem is solved, possibly Monday. The science data is unaffected, but we do not have access to the computer drives that hold the images.

Thursday, August 16, 2012

Movies of erupting CMEs from SDO/AIA were used in the new music video by the band Dispatch - "Circles Around the Sun"! You can see the video here, which was filmed mostly at the VLA and uses a lot of historic NASA footage and movies of the aurora filmed from the ISS.
Dispatch - Circles Around the Sun

Also, today is the anniversary of a small space weather outage in Canada. On August 16, 1989 the Toronto stock exchange was disabled by a geomagnetic storm. This followed on the massive outage in March 1989 that interrupted electrical distribution throughout Quebec. This geomagnetic storm was caused by a coronal mass ejection from a very large X20 solar flare seen on August 16, 1989, which was even stronger than the X15 flare on March 6, 1989 that heralded the earlier storm.
Microchips failed in August 1989 rather than the electrical grid. It affected many fewer people than the 6 million who were left without electricity in March. But it shows the many ways that space weather affects our society. What about the current solar cycle, #24? The Sun appears to have reached peak activity for Solar Cycle 24 in its northern hemisphere. The south continues to produce more and more sunspots. During the decline of a solar cycle the sunspots tend to last longer and the coronal mass ejections can cause large geomagnetic storms. Even though large flares are the heralds of violent space weather, it is the geomagnetic storms that interfere with power grids.
Solar Cycle 24 continues to follow the path of a below average cycle. It is also the best-studied solar cycle, with SDO, SoHO, both STEREO spacecraft, Hinode and numerous ground-based telescopes watching this cycle grow. We study the Sun to know when space weather happens and to learn how to predict it. The images from AIA and HMI are just the beginning of the science of SDO!